Clinical trials have demonstrated the effectiveness of strategies for primary care management of depression, yet adoption of these strategies has been disappointing. This effectiveness study proposes a group randomized trial with intention to treat analysis to test two different approaches to quality improvement for depression (compared to usual care) in community-based primary care practices. Both interventions will be aimed at improving physician use of best practices for depression care. The Dep/QI targets depression using a QI model that was previously successful in providing practices with a process to initiate change and implement evidence-based depression care tools. A Dep/QI facilitator will work with practices in this arm to initiate QI procedures to address depression care. The Dep/QI facilitator will work with each practice over six months and assist the QI team with activities to strengthen the ability of the team to initiate depression interventions within the practice. The Chron/QI intervention assumes a broader focus and seeks to improve organizational capacity to implement chronic care systems that enable primary care physicians to provide evidence-based care for depression as well as other chronic conditions. The Chron/QI will incorporate an innovative Multimethod Assessment Process (MAP) to address critical barriers to improving a practice's capacity for providing chronic care for depression and capacity for making and sustaining change in practice operations. The MAP process has been used successfully to assess and feedback information on practice organization and functioning for preventive services and for diabetes care. A QI facilitator will work with the practices to process the information from the MAP assessment and form a QI team that includes key stakeholders (including patients) to address both organizational function of the practice and the development of office systems to support best practices depression care. Trial endpoints will be measured at baseline and six months to assess adoption and at 12 and 18 months to assess sustainability of intervention effects. Endpoints will include measures of change in practice structure and processes consistent with the chronic care model and demonstrated "best practices" for depression care received by patients with depression as assessed by chart audit. A multimethod assessment will analyze all qualitative and quantitative data separately to understand which components of the interventions were most effective and how they might be further improved, as well as how the practices used the two interventions and how intervention components interacted with key practice characteristics. A specific aim of the multimethod assess will seek to understand how primary care physicians and practices determine and act on the relative priority of depression care among the competing demands of primary care.